Fluid streams, such as air and liquid, carry contaminant material therein, such as gas phase contaminants and liquid and solid particulates. In many instances, it is desired to filter some or all of the contaminant material from the fluid stream. For example, air streams to engines for motorized vehicles or for power generation equipment, air and gas streams to gas turbine systems, air and gas streams to various combustion furnaces, and air and gas streams to heat exchangers (e.g., heating and air conditioning) carry particulate contaminants that should often be filtered. Liquid streams in engine lube systems, hydraulic systems, coolant systems and fuel systems, can also carry contaminants that should be filtered. It is preferred for such systems that selected contaminant material be removed from (or have its level reduced in) the fluid.
A variety of fluid filters (gas or liquid filters) have been developed for contaminant reduction. In general, however, continued improvements are sought. One example of fluid filters that have excellent performance in some implementations are filters containing z-media. Z-media generally refers to a type of fluted filtering media element where a fluid enters flutes on a first face of the media element and exits from flutes at a second face of the media element. In general, the faces on z-media are provided on opposite ends of the media. The fluid enters through open flutes on one face and exits through open flutes on the other face in some embodiments (such as for particulate filtration). At some point between the first face and the second face, the fluid passes from one flute to another flute to provide for filtration.
Existing flute designs for z-media, as well as equipment for making the flutes, are suitable for many implementations. However, improvements are still desired, and are the subject of the present invention.